What Factors Affect Breast Cancer Neoadjuvant Chemotherapy Efficacy?

What Are the Factors Affecting Neoadjuvant Chemotherapy Efficacy in Breast Cancer? A Non-invasive in Vivo Study Using Specialist Magnetic Resonance (MR) Methods

Breast cancer is the most prevalent cancer affecting women. To treat locally advanced breast cancers, neoadjuvant chemotherapy (NACT) is often carried out before surgery to reduce the tumour size to allow breast conservation surgery. However, treatment response for individual patients varies, where the tumour may not respond to treatment and the quality of patient care is compromised if the NACT treatment plan is not optimised. Therefore, the assessment of NACT efficacy is beneficial for the early identification of these patients and appropriate management of treatment.

Breast tumours have unique features compared to healthy tissue, including abnormal tissue structure and biochemical composition. With NACT there are specific changes to such tumour features indicating tumour treatment response.

The purpose of this study is to establish how the changes to breast tumour features following NACT treatment are seen in non-invasive imaging. This study will look at scans of breast tumours using magnetic resonance imaging (MRI). Changes to tissue structure will be measured by advanced diffusion MRI techniques and changes to tumour related biochemical substances will be measured by advanced magnetic resonance spectroscopy techniques. The investigators aim to assess if these techniques can provide information on the tumour treatment response following subsequent rounds of NACT treatment.

In this longitudinal study, 25 patients undergoing NACT will be recruited for four repeated MRI investigations over the course of NACT treatment. Magnetic resonance (MR) measurements of tissue microstructure and biochemical composition will be compared against histological measurements and radiological assessments of treatment response.

The study will recruit patients undergoing treatment at the NHS Grampian. This research is funded by Friends of ANCHOR, Tenovus Scotland Grampian and the NHS Grampian Endowment Research Fund.

In this single group longitudinal study, the investigators propose that functional images from magnetic resonance (MR) methods performed at baseline and after 6 cycles of neoadjuvant chemotherapy (NACT) are in agreement with histological findings from pre-treatment biopsy and post-treatment surgically excised tissue. MR methods will be performed at baseline (pre-treatment) and after the 1st, 3rd and 6th (post-treatment) cycles of NACT treatment. The investigators hypothesise that specific physiological changes detected through MR methods are a manifestation of tumour response to NACT confirmed by histology and radiological assessment (Hypothesis 1). The investigators further hypothesise that early sensitivity to physiological changes manifesting from tumour response to NACT can be revealed by MR measurements after the first and third cycle of treatment (Hypothesis 2).

Research Question 1: Is there a difference in physiological parameters revealed by MR measurements at baseline and after completion of NACT?

Research Question 2: Do the physiological measurements at the completion of NACT from MR measures agree with histological findings?

Research Question 3: Is there a difference between MR measurements at baseline and after the first and third cycle of NACT?

Research Question 4: Is there a difference in MR measurements at baseline, first and third cycle of NACT, between positive treatment responders and non-responders.

MR measurements will be compared against clinical and study specific results from histological analysis and radiological assessment of MRI, mammography and ultrasound measures of tumour treatment response. Information collected from a health questionnaire will supplement interpretation of the data.

To test the effects of NACT on specific aspects of tumour physiology, paired t-tests will be performed on MR measures of lactate concentration, lipid composition and diffusion parameters, between baseline and post-treatment assessments (Research Question 1).

To examine the relationship between MR measurements and histology, correlation analysis will be conducted between baseline and post-treatment assessments. MR measures will be correlated against corresponding percentage changes in histological findings between biopsy and tumour excision (Research Question 2).

To evaluate MR measures as early markers of NACT efficacy, paired t-tests will be carried out between MR measures at pre-treatment and post 1st and 3rd cycles of NACT treatment (Research Question 3), with independent group difference determined between responders and non-responders (Research Question 4).

Inclusion Criteria:

• Patients with pathologically confirmed invasive breast cancer undergoing neoadjuvant chemotherapy and surgery.

Exclusion Criteria:

• Condition to contradictive to MRI investigation with contrast agent (poor renal function, contrast agent allergy, metal implants or pace maker).
• Started hormone or chemotherapy treatment before recruitment.
• Undergoing treatment for concurrent cancer diagnosis.
• Marker coil contradictive to MRI investigation.